1b.Approach (from AD-416)
Test more environmentally acceptable pesticides and compounds for use in control or eradication programs for fruit flies. Investigate biology and behavior of fruit flies and their parasitoids. Evaluate augmentative parasite releases, mass trapping, male annihilation, sterile fly releases, novel insecticides and food bait sprays as control, suppression, or eradication technologies. Develop new or improved lures, attractants, parapheromones, and baits to be used in improved trap detection devices and/or control systems. Investigate fruit fly and parasitoid olfactory, gustatory, and oviposition aensilla and their electrophysiology. Investigate chemical structure and activity relationships of semiochemicals of fruit flies and their biocontrol agents. Formerly 5320-22430-020-00D (3/05).

3.Progress Report
Identifying Control Technologies for Bactrocera latifrons. Although Bactrocera latifrons have been established in Hawaii for over 20 years, little research had been directed toward methods of control of this species. Through research efforts by scientists at the Tropical Crop and Commodity Protection Research Unit, the U.S. Pacific Basin Agricultural Research Center and at the University of Hawaii, potentials for control were documented in the areas of biological control, male annihilation and use of bait sprays. Natural parasitizatin rates of B. latifrons were found to be very low in Hawaii suggesting that efforts to improve the effectiveness of biological control against B. latifrons may help in the field.

Further evaluations are continuing on the development of new and improved lures for fruit flies and moths. Research is focused on application and formulation improvements using male lures and new female lures for fruit flies and pheromones for moths. Identified moth pheromone of the nettle caterpillar is currently utilized for detection, delimination, monitoring and control in newly infested areas of Oahu, HI and also areas with established populations. Novel approaches to mating disruption (mobile mating disruption (MMD)) for moth control suggest that cross species application of moth pheromone is possible. A few formulation changes to improved male attractants have been implemented. Improved male attractants were effectively evaluated in non-toxicant traps. Female attractants for melon fly are continuing to outperform protein bait in open field tests.

4.Accomplishments
1.
Spinosad Replacement for Organophosphate Male Annihilation Treatments in California. Overuse of organophosphate and carbamate insecticides have been implicated in secondary pest outbreaks, negative effects on beneficial insects, environmental contamination, and adverse effects on human health. The Environmental Protection Agency would like to phase out or reduce the use of these insecticides, replacing their function with reduced risk insecticides. Studies were conducted by ARS scientists in the Pacific Basin Agricultural Research Center in Hilo, HI to quantify attraction and feeding response resulting in mortality of the male oriental fruit fly to a novel male annihilation treatment (MAT) formulation. In comparison with the method currently used in California and Florida. Our results suggest that spinosad with low contact toxicity, and when mixed with a pheromone, insect lure and methyl eugenol offers a reduced-risk alternative for control of oriental fruit fly, without many of the negative effects to humans and non-targets of broad spectrum contact poisons such as naled. This foundation offers potential for control of males in an area-wide integrated pest management (IPM) system without the need for conventional organophosphates.

2.
Novel Fruit Fly Monitoring Trap Dispensers. Fruit flies are among the most economically important pests attacking soft fruits worldwide. Over 40,000 methyl eugenol (ME) and cue-lure (C-L) traps are maintained in California and Florida to detect these flies so they can be eradicated rapidly. Novel solid lure-insecticide dispensers were tested by ARS scientists in the Pacific Basin Agricultural Research Center in Hilo, HI under Hawaiian weather conditions against small populations of oriental and melon fruit flies, respectively. Captures with solid Farma Tech wafer dispensers with ME or C-L and the pesticide dimethyl dichloro-vinyl phosphate (DDVP) placed inside Jackson traps were equal to those for Jackson traps with naled currently used for detection of ME and C-L responding fruit flies on the U.S. mainland. Farma Tech solid ME and C-L wafers with DDVP would be more convenient and safer to handle than current liquid lure-insecticide formulations (e.g. naled) used for detection programs in Florida and California.

3.
Identifying roosting hosts for melon fly and for oriental fruit fly. Identification of roosting sites of melon fly (Bactrocera cucurbitae) and oriental fruit fly (Bactrocera dorsalis) is of critical importance for use as bait application sites that will give the best population suppression. Suppression can be improved if it is ensured that preferred roosting sites are present in a cropping environment. Ideally, roosting hosts must be attractive to the fly species as well as acceptable to the grower. One potential border plant of interest to some growers is cassava, Manihot esculenta, because it could serve as a food crop as well as a roosting host. Field tests conducted by ARS scientists in Hilo, HI demonstrated that there was no significant difference in the use of cassava by either melon fly or oriental fruit fly as a roosting host compared to their use of castor bean, Ricinus communis, a known favored roosting host. These results provide guidance for farm design for improved suppression of melon fly and oriental fruit fly.

4.
Tracking the movement distance of oriental fruit fly. Suppression of tephritid fruit fly populations in an area may be futile if source populations outside of that area are capable of moving into and re-establishing populations within the suppression area. A study was conducted by ARS scientists in Hilo, HI in association with an oriental fruit fly suppression trial in commercial papaya orchards in the Puna District on the island of Hawaii with an aim to see from what distances oriental fruit flies could travel to enter the suppression zone. Four releases of double-marked, sterile, laboratory-reared oriental fruit flies were completed at four different distances from the suppression zone. Flies captured in oriental fruit fly male lure traps (baited with methyl eugenol) and protein bait traps were collected and examined for the mark. Many flies were recovered at unprecedented distances (2 – 11.39 km). These results aid in understanding the long tails of spatial distribution of fly movement that have been suspected for this species, and will benefit consideration of dimensions for buffer zones that would be needed for the establishment of infestation free or low prevalence zones.